Visual Perception is a Fundamental aspect of human cognition. Perceptual tasks that at first may seem trivial can be overwhelmingly difficult and require immense processing. One such example is object persistence - the ability to represent visual entities as the same objects from one moment to the next. Coherent perception requires not only parsing incoming information into discrete units (i.e. forming object representations), but also tracking the unit as the same persisting individuals over time and motion (i.e., forming persisting object representations). A new and intuitive theory is offered, suggesting that object persistence operates intelligently: alternating between being flexible or constrained, depending on what is most advantageous. Object persistence is explored here via object files - visual representations that track entities over time and motion as the same objects, and store (and update) information about the objects. The object-reviewing paradigm is used to test object files: In this paradigm, a preview of information on a specific object leads to speeded processing of that information when it later reappear on the same object (even if in a location) compared to on a different object. This response time advantages provides and operational measure of persistence. Three specific Aims explore the flexibility and constraints of object file: Specific aim #1 examines whether object persistence is guided by the principles of boundedness and cohesion, two specific constraints that influence infant object cognition. Specific Aim #2 tests object files' flexibility by exploring whether 'files' are established for noncanonical objects that are perceptually grouped (e.g. testing for group files). Finally, Specific Aim #3 explores whether top-down knowledge can influence object file processing. Many current adult developmental theories rely upon an understanding of object persistence and have thus created the ideal environment for this R03 proposal: this work is both timely and needed as it will directly inform both literatures and will provide useful for a variety of other fields as well. By exploring this understudied topic with a new theoretical approach the proposed studies will work to establish a solid research enterprise that will be fruitful for years to come. Given the limited research to date directly exploring object persistence, its ultimate role for mental health issues remains an important mystery. By testing the limits of the system under the umbrella of a global theory, these studies will establish a firmer understanding of the basic science, and only though such explorations can the field move forward to offer an important tool for mental health research. [unreadable] [unreadable] [unreadable]